I think the sign up is because users of the free product (apart from getting ads) have restrictions around how much music can be listened to - i think it's 10 hours per month
You will most certainly have to register with Spotify and will be subjected to regular charges which no doubt will be dependent on what you download as a member.
The site is Not my scene, so I am unable to recommend it; although it would appear to be a safe site.
In the link which I have given above ^^^ it does indicate that you would have to pay for the Premium edition to 'Download Music and Listen Off-line'.
Consequently, it is my view that unless you opt for 'Premium' and download to an audio file in your computer, you will Not be able to transfer music to disc.
It would be interesting to hear the views of others.
///I think the sign up is because users of the free product (apart from getting ads) have restrictions around how much music can be listened to - i think it's 10 hours per month
Hence the 'account'///
I use the free version of Spotify and for some strange reason I don't get adverts at all on it, I had them for the first few weeks and then they just stopped :)